Boss VF-1 Effect Processor

okay now i'm lost, so okay for example a fc-50, okay lets say i'm 
playing right and i have a fc-50 all set up to a vf-1 and the 
beginnig of the song is a clean guitar sound okay here comes chorus 
of the song and it's the same guitar setting just with amp(dist) on, 
instead of off... can i just hit one of the foot switches to turn it 
on, instead of having to change the patch number. and if yes can each 
switch be a different effect like 1. amp 2. mod 3.chorus 4.delay 
5.compressor, u know what i mean :p
basically does it allow real time control of the current patch 
variables. sorry not very good with midi devices.
thanks,
blur